Prevent bots and guests from viewing forum?

[Jesse17]

I can't believe I can't find an answer for this, but I've been searching and reading for hours now.

Our forum is private. Someone can register, but can only view/post in one board, the welcome section, until they're buzzed in by an admin to a higher membership level to see the rest of the forum. But the members are having a fit because it constantly says there is 6-8 "Guests" viewing the forum. Most say they are viewing the forum index, which I assume means they can only see the Welcome section but some say they are viewing threads that are in the more private parts of the forum.

I've set up a robot.txt file with:
User-agent: *
Disallow: /

I've unchecked the "allow guest to brows the forum" box.
I've installed the "Hade Topics from Guests" mod that is suppose to redirect to the log in page if a guest clicks on a topic.
I've made a couple other changes I can't remember now.

And still there is ALWAYS 6, 7, 9 "guests" viewing the forum and at least one or two says they're viewing a thread that is suppose to be private. Even in Maintenance mode is shows the same guests viewing the forums.

What else can I do? Please!

[Aleksi "Lex" Kilpinen]

There's no need to worry. The guests shown are simply seeing the "You need to be registered..." notice. They can not see the contents of the forums. They have still accessed index.php and are counted.
You can try, just log out and try to access any topic you wish. For this, you don't even need any mods if you have unchecked the "Allow guests" setting.

[Jesse17]

There's no need to worry. The guests shown are simply seeing the "You need to be registered..." notice. They can not see the contents of the forums. They have still accessed index.php and are counted.
You can try, just log out and try to access any topic you wish. For this, you don't even need any mods if you have unchecked the "Allow guests" setting.

I would assume that if it said they were all viewing the forum index, but what about the one or two that say they're viewing a particular thread that is in one of the private boards?

[Kindred]

it just means that they have tried to access that URL.

If they don't have access to the contents, then they will get a "not allowed" message, but the system will still track that they have that URL loaded and show them "viewing message 1234"

[efk]

2 more things, if there is some unused archived board as child-board and its without purpose, but its not hidden from guests, bots or spiders or something like that can still find them, and with this all boards/path will be accessible on click with result "not allowed" message. 2nd thing, logged out users trying to go join your forum with 1 click, from browser history suggested list.
So if you check Who's Online, you can easily determine if your guests are real users or bots with simple checking their IP on google, unless they are using vpn.

And still there is ALWAYS 6, 7, 9 "guests" viewing the forum

Most likely this is the number of bots, spiders or something like that who are trying to visit something without success. In other case if you have very active forum, like for example SMF forum, then it can be users who failing to join with single click, so they have to log in, but you can follow they IP, if they log in, you can see it depends on how active your forum is, more guests/harder to track and understand. It could be also logged out user who did not closed tab on his browser, but forum may show last topic where user was, or forum just goes blind mode and is still showing presence of activity even if user tab is closed. This depends on Who's Online time, usually is 15 minutes, but if increased for example to 30 minutes, it can give you results for someone who was active about 29 minutes ago and you may think something is wrong.